OpenRaiser/Intern-Atlas huggingface dataset:
Promoting Game Accessibility: Experiencing an Induction on Inclusive Design Practice at the Global Games Jam
Venue: arXiv cs.CY 2013
Year: 2013

The Global Games Jam (GGJ) attracts many people who are passionate about games development, coming from a range of educational backgrounds. Therefore, the event can be experienced by novices and student developers as an opportunity for learning. This provides an opening to promote themes and ideas that could help form future thinking about games design, emerging as a form of induction on key design issues for new practitioners. Such an approach aims to raise awareness about issues which learners could help develop and take with them into industry. However, the experience itself affords a deep experiential rhetoric and dialogue with experts that could be an effective pedagogical tool for issues seldom addressed deeply in formal educational settings. This paper describes an account by one such individual, being introduced to game accessibility through participation in the GGJ. As such, it is not intended as a rigorous empirical analysis, but rather a perspective on one way a game jam can be experienced, inviting further research on the topic.
Parallelizing Stream with Future
Venue: arXiv cs.DC 2013
Year: 2013

Stream is re-interpreted in terms of a Lazy monad. Future is substituted for Lazy in the obtained construct, resulting in possible parallelization of any algorithm expressible as a Stream computation. The principle is tested against two example algorithms. Performance is evaluated, and a way to improve it briefly discussed.
Realized collaboration across borders - Linux and the bioinformatic part
Venue: arXiv cs.CY 2013
Year: 2013

In year 2006 Biolinux inter alia with the work of Tim Booth gives its rise and provide an operating system that was and is specialized in providing an environment for the needs of bioinformatics. Since than some years have been seen and the information about Biolinux has not only widespread within the bio-science community, also the Linux community at whole had a ear for it. This has caused a process called collaboration across borders and makes as the keywords say the different work groups cooperating together. In this paper we will have a look into the history of this collaboration, will show its growth until we reach the actual state and we will talk about the quo vadis of this process.
Correcting self-intersecting polygons using minimal memory A simple and efficient algorithm and thoughts on line-segment intersection algorithms
Venue: arXiv cs.CG 2013
Year: 2013

While well-known methods to list the intersections of either a list of segments or a complex polygon aim at achieving optimal time-complexity they often do so at the cost of memory comsumption and complex code. Real-life software optimisation however lies in optimising at the same time speed and memory usage as well as keeping code simple. This paper first presents some thoughts on the available algorithms in terms of memory usage leading to a very simple scan-line-based algorithm aiming at answering that challenge. Although sub-optimal in terms of speed it is optimal if both speed and memory space are taken together and is very easy to implement. For N segments and k intersections it uses only N additional integers and lists the intersections in O(N^1.26) or corrects them in O((N+k) N^0.26) at most in average, with a high probability of a much lower exponent around 0.16 and even as low as 0.1. It is therefore well adapted for inclusion in larger software and seems like a good compromise. Worst-case is in O(N^2). Then the paper will focus on differences between available methods and the brute-force algorithm and a solution is proposed. Although sub-optimal its applications could mainly be to answer in a fast way a number of scattered unrelated intersection queries using minimal complexity and additional resources.
On BC-trees and BC-subtrees
Venue: arXiv cs.DM 2013
Year: 2013

A BC-tree (block-cutpoint-tree) is a tree (with at least two vertices) where the distance between any two leaves is even. Motivated from the study of the "core" of a graph, BC-trees provide an interesting class of trees. We consider questions related to BC-trees as an effort to make modest progress towards the understanding of this concept. Constructive algorithms are provided for BC-trees with given order and number of leaves whenever possible. The concept of BC-subtrees is naturally introduced. Inspired by analogous work on trees and subtrees, we also present some extremal results and briefly discuss the "middle part" of a tree with respect to the number of BC-subtrees.
Enabling Self-Powered Autonomous Wireless Sensors with New-Generation I2C-RFID Chips
Venue: arXiv cs.OH 2013
Year: 2013

A self-powered autonomous RFID device with sensing and computing capabilities is presented in this paper. Powered by an RF energy-harvesting circuit enhanced by a DC-DC voltage booster in silicon-on-insulator (SOI) technology, the device relies on a microcontroller and a new generation I2C-RFID chip to wirelessly deliver sensor data to standard RFID EPC Class-1 Generation-2 (Gen2) readers. When the RF power received from the interrogating reader is -14 dBm or higher, the device, fabricated on an FR4 substrate using low-cost discrete components, is able to produce 2.4-V DC voltage to power its circuitry. The experimental results demonstrate the effectiveness of the device to perform reliable sensor data transmissions up to 5 meters in fully-passive mode. To the best of our knowledge, this represents the longest read range ever reported for passive UHF RFID sensors compliant with the EPC Gen2 standard.
Secure Biometrics: Concepts, Authentication Architectures and Challenges
Venue: arXiv cs.CR 2013
Year: 2013

BIOMETRICS are an important and widely used class of methods for identity verification and access control. Biometrics are attractive because they are inherent properties of an individual. They need not be remembered like passwords, and are not easily lost or forged like identifying documents. At the same time, bio- metrics are fundamentally noisy and irreplaceable. There are always slight variations among the measurements of a given biometric, and, unlike passwords or identification numbers, biometrics are derived from physical characteristics that cannot easily be changed. The proliferation of biometric usage raises critical privacy and security concerns that, due to the noisy nature of biometrics, cannot be addressed using standard cryptographic methods. In this article we present an overview of "secure biometrics", also referred to as "biometric template protection", an emerging class of methods that address these concerns.
Extending Sitemaps for ResourceSync
Venue: arXiv cs.DL 2013
Year: 2013

The documents used in the ResourceSync synchronization framework are based on the widely adopted document format defined by the Sitemap protocol. In order to address requirements of the framework, extensions to the Sitemap format were necessary. This short paper describes the concerns we had about introducing such extensions, the tests we did to evaluate their validity, and aspects of the framework to address them.
Improving NSGA-II with an Adaptive Mutation Operator
Venue: arXiv cs.NE 2013
Year: 2013

The performance of a Multiobjective Evolutionary Algorithm (MOEA) is crucially dependent on the parameter setting of the operators. The most desired control of such parameters presents the characteristic of adaptiveness, i.e., the capacity of changing the value of the parameter, in distinct stages of the evolutionary process, using feedbacks from the search for determining the direction and/or magnitude of changing. Given the great popularity of the algorithm NSGA-II, the objective of this research is to create adaptive controls for each parameter existing in this MOEA. With these controls, we expect to improve even more the performance of the algorithm. In this work, we propose an adaptive mutation operator that has an adaptive control which uses information about the diversity of candidate solutions for controlling the magnitude of the mutation. A number of experiments considering different problems suggest that this mutation operator improves the ability of the NSGA-II for reaching the Pareto optimal Front and for getting a better diversity among the final solutions.
Propositional Encoding of Constraints over Tree-Shaped Data
Venue: arXiv cs.PL 2013
Year: 2013

We present a functional programming language for specifying constraints over tree-shaped data. The language allows for Haskell-like algebraic data types and pattern matching. Our constraint compiler CO4 translates these programs into satisfiability problems in propositional logic. We present an application from the area of automated analysis of (non-)termination of rewrite systems.
Implications for Utilizing YouTube based Community Interactions for Destination Marketing
Venue: arXiv cs.CY 2013
Year: 2013

In recent time, YouTube has evolved into a powerful medium for social interaction. Utilizing YouTube for enhancing marketing endeavors is a strategy practiced by marketing professionals across several industries. This paper rationalizes on the different ways and means of leveraging YouTube-based platforms for effective destination marketing by the hospitality industry (hotels). More specifically, the typology of virtual communities is adapted to evaluate the YouTube platform for effective destination marketing. Comments made by YouTube users have been subjected to a content analysis and the results are reported here under the five broad clusters of virtual communities. Implications for utilizing YouTube-based community interactions for destination marketing are also highlighted as part of the outcome of this research.
Towards Rational Deployment of Multiple Heuristics in A*
Venue: arXiv cs.AI 2013
Year: 2013

The obvious way to use several admissible heuristics in A* is to take their maximum. In this paper we aim to reduce the time spent on computing heuristics. We discuss Lazy A*, a variant of A* where heuristics are evaluated lazily: only when they are essential to a decision to be made in the A* search process. We present a new rational meta-reasoning based scheme, rational lazy A*, which decides whether to compute the more expensive heuristics at all, based on a myopic value of information estimate. Both methods are examined theoretically. Empirical evaluation on several domains supports the theoretical results, and shows that lazy A* and rational lazy A* are state-of-the-art heuristic combination methods.
A Truth Serum for Sharing Rewards
Venue: arXiv cs.GT 2013
Year: 2013

We study a problem where a group of agents has to decide how a joint reward should be shared among them. We focus on settings where the share that each agent receives depends on the subjective opinions of its peers concerning that agent's contribution to the group. To this end, we introduce a mechanism to elicit and aggregate subjective opinions as well as for determining agents' shares. The intuition behind the proposed mechanism is that each agent who believes that the others are telling the truth has its expected share maximized to the extent that it is well-evaluated by its peers and that it is truthfully reporting its opinions. Under the assumptions that agents are Bayesian decision-makers and that the underlying population is sufficiently large, we show that our mechanism is incentive-compatible, budget-balanced, and tractable. We also present strategies to make this mechanism individually rational and fair.
Stochastic Parity Games on Lossy Channel Systems
Venue: arXiv cs.GT 2013
Year: 2013

We give an algorithm for solving stochastic parity games with almost-sure winning conditions on lossy channel systems, for the case where the players are restricted to finite-memory strategies. First, we describe a general framework, where we consider the class of 2.5-player games with almost-sure parity winning conditions on possibly infinite game graphs, assuming that the game contains a finite attractor. An attractor is a set of states (not necessarily absorbing) that is almost surely re-visited regardless of the players' decisions. We present a scheme that characterizes the set of winning states for each player. Then, we instantiate this scheme to obtain an algorithm for stochastic game lossy channel systems.
Markov two-components processes
Venue: arXiv cs.SY 2013
Year: 2013

We propose Markov two-components processes (M2CP) as a probabilistic model of asynchronous systems based on the trace semantics for concurrency. Considering an asynchronous system distributed over two sites, we introduce concepts and tools to manipulate random trajectories in an asynchronous framework: stopping times, an Asynchronous Strong Markov property, recurrent and transient states and irreducible components of asynchronous probabilistic processes. The asynchrony assumption implies that there is no global totally ordered clock ruling the system. Instead, time appears as partially ordered and random. We construct and characterize M2CP through a finite family of transition matrices. M2CP have a local independence property that guarantees that local components are independent in the probabilistic sense, conditionally to their synchronization constraints. A synchronization product of two Markov chains is introduced, as a natural example of M2CP.
FOLE: The First-order Logical Environment
Venue: arXiv cs.LO 2013
Year: 2013

This paper describes the first-order logical environment FOLE. Institutions in general, and logical environments in particular, give equivalent heterogeneous and homogeneous representations for logical systems. As such, they offer a rigorous and principled approach to distributed interoperable information systems via system consequence. Since FOLE is a particular logical environment, this provides a rigorous and principled approach to distributed interoperable first-order information systems. The FOLE represents the formalism and semantics of first-order logic in a classification form. By using an interpretation form, a companion approach defines the formalism and semantics of first-order logical/relational database systems. In a strict sense, the two forms have transformational passages (generalized inverses) between one another. The classification form of first-order logic in the FOLE corresponds to ideas discussed in the Information Flow Framework (IFF). The FOLE representation follows a conceptual structures approach, that is completely compatible with formal concept analysis and information flow.
Tight Upper and Lower Bounds to the Information Rate of the Phase Noise Channel
Venue: arXiv cs.IT 2013
Year: 2013

Numerical upper and lower bounds to the information rate transferred through the additive white Gaussian noise channel affected by discrete-time multiplicative autoregressive moving-average (ARMA) phase noise are proposed in the paper. The state space of the ARMA model being multidimensional, the problem cannot be approached by the conventional trellis-based methods that assume a first-order model for phase noise and quantization of the phase space, because the number of state of the trellis would be enormous. The proposed lower and upper bounds are based on particle filtering and Kalman filtering. Simulation results show that the upper and lower bounds are so close to each other that we can claim of having numerically computed the actual information rate of the multiplicative ARMA phase noise channel, at least in the cases studied in the paper. Moreover, the lower bound, which is virtually capacity-achieving, is obtained by demodulation of the incoming signal based on a Kalman filter aided by past data. Thus we can claim of having found the virtually optimal demodulator for the multiplicative phase noise channel, at least for the cases considered in the paper.
NEMESYS: Enhanced Network Security for Seamless Service Provisioning in the Smart Mobile Ecosystem
Venue: arXiv cs.NI 2013
Year: 2013

As a consequence of the growing popularity of smart mobile devices, mobile malware is clearly on the rise, with attackers targeting valuable user information and exploiting vulnerabilities of the mobile ecosystems. With the emergence of large-scale mobile botnets, smartphones can also be used to launch attacks on mobile networks. The NEMESYS project will develop novel security technologies for seamless service provisioning in the smart mobile ecosystem, and improve mobile network security through better understanding of the threat landscape. NEMESYS will gather and analyze information about the nature of cyber-attacks targeting mobile users and the mobile network so that appropriate counter-measures can be taken. We will develop a data collection infrastructure that incorporates virtualized mobile honeypots and a honeyclient, to gather, detect and provide early warning of mobile attacks and better understand the modus operandi of cyber-criminals that target mobile devices. By correlating the extracted information with the known patterns of attacks from wireline networks, we will reveal and identify trends in the way that cyber-criminals launch attacks against mobile devices.
Fast Autocorrelated Context Models for Data Compression
Venue: arXiv cs.IT 2013
Year: 2013

A method is presented to automatically generate context models of data by calculating the data's autocorrelation function. The largest values of the autocorrelation function occur at the offsets or lags in the bitstream which tend to be the most highly correlated to any particular location. These offsets are ideal for use in predictive coding, such as predictive partial match (PPM) or context-mixing algorithms for data compression, making such algorithms more efficient and more general by reducing or eliminating the need for ad-hoc models based on particular types of data. Instead of using the definition of the autocorrelation function, which considers the pairwise correlations of data requiring O(n^2) time, the Weiner-Khinchin theorem is applied, quickly obtaining the autocorrelation as the inverse Fast Fourier transform of the data's power spectrum in O(n log n) time, making the technique practical for the compression of large data objects. The method is shown to produce the highest levels of performance obtained to date on a lossless image compression benchmark.
An Intelligent System to Detect, Avoid and Maintain Potholes: A Graph Theoretic Approach
Venue: arXiv cs.AI 2013
Year: 2013

In this paper, we propose a conceptual framework where a centralized system, classifies the road based upon the level of damage. The centralized system also identifies the traffic intensity thereby prioritizing the roads that need quick action to be taken upon. Moreover, the system helps the driver to detect the level of damage to the road stretch and route the vehicle from an alternative path to its destination. The system sends a feedback to the concerned authorities for a quick response to the condition of the roads. The system we use comprises a laser sensor and pressure sensors in shock absorbers to detect and quantify the intensity of the pothole, a centralized server which maintains a database of locations of all the potholes which can be accessed by another unit inside the vehicle. A point to point connection device is also installed in vehicles so that, when a vehicle detects a pothole which is not in the database, all the vehicles within a range of 20 meters are warned about the pothole. The system computes a route with least number of potholes which is nearest to the desired destination . If the destination is unknown, then the system will check for potholes in the current road and displays the level of damage. The system is flexible enough that the destination can be added, removed or changed any time during the travel. The best possible route is suggested by the system upon the alteration. We prove that the algorithm returns an efficient path with least number of potholes.
The Promise Polynomial Hierarchy
Venue: arXiv cs.CC 2013
Year: 2013

The polynomial hierarchy is a grading of problems by difficulty, including P, NP and coNP as the best known classes. The promise polynomial hierarchy is similar, but extended to include promise problems. It turns out that the promise polynomial hierarchy is considerably simpler to work with, and many open questions about the polynomial hierarchy can be resolved in the promise polynomial hierarchy. Our main theorem is that, in the world of promise problems, if phi has a weak (Turing, Cook) reduction to SAT then phi has a strong (Karp, many-one) reduction to UVAL2, where UVAL2(f) is the promise problem of finding the unique x such that f(x,y)=1 for all y. We also give a complete promise problem for the promise problem equivalent of UP intersect coUP.
Finite-Length and Asymptotic Analysis of Correlogram for Undersampled Data
Venue: arXiv cs.IT 2013
Year: 2013

This paper studies a spectrum estimation method for the case that the samples are obtained at a rate lower than the Nyquist rate. The method is referred to as the correlogram for undersampled data. The algorithm partitions the spectrum into a number of segments and estimates the average power within each spectral segment. This method is able to estimate the power spectrum density of a signal from undersampled data without essentially requiring the signal to be sparse. We derive the bias and the variance of the spectrum estimator, and show that there is a tradeoff between the accuracy of the estimation, the frequency resolution, and the complexity of the estimator. A closed-form approximation of the estimation variance is also derived, which clearly shows how the variance is related to different parameters. The asymptotic behavior of the estimator is also investigated, and it is proved that this spectrum estimator is consistent. Moreover, the estimation made for different spectral segments becomes uncorrelated as the signal length tends to infinity. Finally, numerical examples and simulation results are provided, which approve the theoretical conclusions.
To Reserve or Not to Reserve: Optimal Online Multi-Instance Acquisition in IaaS Clouds
Venue: arXiv cs.DC 2013
Year: 2013

Infrastructure-as-a-Service (IaaS) clouds offer diverse instance purchasing options. A user can either run instances on demand and pay only for what it uses, or it can prepay to reserve instances for a long period, during which a usage discount is entitled. An important problem facing a user is how these two instance options can be dynamically combined to serve time-varying demands at minimum cost. Existing strategies in the literature, however, require either exact knowledge or the distribution of demands in the long-term future, which significantly limits their use in practice. Unlike existing works, we propose two practical online algorithms, one deterministic and another randomized, that dynamically combine the two instance options online without any knowledge of the future. We show that the proposed deterministic (resp., randomized) algorithm incurs no more than 2-alpha (resp., e/(e-1+alpha)) times the minimum cost obtained by an optimal offline algorithm that knows the exact future a priori, where alpha is the entitled discount after reservation. Our online algorithms achieve the best possible competitive ratios in both the deterministic and randomized cases, and can be easily extended to cases when short-term predictions are reliable. Simulations driven by a large volume of real-world traces show that significant cost savings can be achieved with prevalent IaaS prices.